An oil component has conventionally been added to drinks, foods, cosmetics, pharmaceutical products and the like. However, the oil component is insoluble or scarcely-soluble in water. For this reason, the oil component has generally been mixed as a so-called emulsion with an aqueous medium by using a certain emulsification means. An emulsion scatters light depending on its particle diameter. Therefore, the emulsion and foods and cosmetics having the emulsion added thereto are turbid, and the turbidity may be not preferred on appearance. As a result, it has been desired to decrease the particle diameter of the emulsion to such an extent that light scattering becomes insignificant. Furthermore, the emulsion is generally in a semi-stable state, and has had great problems in that the particle diameter is increased during storage to cause separation of the water phase and the oil phase during long-term storage.
On the other hand, in recent years, many commercial products such as foods and cosmetics containing various nutritionally functional materials are present, accompanying the boom in healthcare commercial products. Even in the commercial products, such as foods and cosmetics, it has become apparent that if the commercial products contain lipid-soluble nutritionally functional materials that are insoluble or scarcely-soluble in water, there are various problems in, for example, deterioration of materials themselves and demulsification during storage as described above.
A method in which a powdered composition is formed through a step of drying an emulsion has been proposed as a method that enables handling of the oil component in more stable state (see, for example, Japanese Patent Application Laid-Open (JP-A) No. 2003-55688). Powderization is a desirable method in the points of improvement of storability due to removal of water, reduction of transportation costs, improvement of handling properties, and the like.
A known use of general-purpose powdered compositions is powder oils and fats, and application examples thereof include bakery goods, frozen foods, western confectionery, Japanese confectionery, fried goods and noodle goods. Flavor (perfume) is known as another example of use, and application examples thereof include chewing gums, powdered drinks, powdered desserts, various toiletry goods and fibers.
JP-A No. 4-262757 discloses a method of powderizing including (i) emulsifying an edible oil material using a film-forming agent containing a mixture of a highly degradable dextrin and a sucrose fatty acid ester, and then (ii) drying. Japanese Patent No. 3302999 discloses a carotenoid composition for foods. The carotenoid composition contains an oil solvent containing carotenoid, a water-dispersible matrix, a stabilizer and a natural emulsifier. In the patent, sucrose, glucose, fructose, mannose, pentose, maltose and maltodextrin are disclosed as matrix materials. Japanese Patent No. 3510552 discloses that, in addition to excipients such as gum arabic, modified starch and cyclodextrin, palatinose or raffinose is added in order to improve perfume retainability and stability against oxidation of perfume powder.